For the emulator I used FCEUX in version 2.6.4. No changed settings. I just booted up the rom and went to Tools > TAS Editor.
This is a warpless run of Super Mario Bros. for the Nintedo Entertainment System. (NES)
CasualPokePlayer: Welcome to the site! We only accept TAS records here, and this run does not beat our current record, so unfortunately we cannot accept it. For future submissions, please make sure that your run is as fast as you can make it. You have infinite tries, you should not be missing tricks at all, and especially for SMB1 there is an extensive amount of other runs that you can watch to learn how to do these things for yourself. Keep at it, though! I hope to see future submissions from you!